Electronic devices, such as laptops, notebooks, netbooks, personal digital assistants (PDAs) and mobile phones, for example, increasingly tend to include a variety of wireless communication capabilities operating at increased data rates. The wireless communication systems used by these devices are expanding into the higher frequency ranges of the communication spectrum, such as, for example, the millimeter wave region and, in particular, the 60 GHz band. Propagation losses and attenuation tend to increase at these higher frequencies, however, and it can become difficult to implement antenna systems in a manner that provides the desired gain and spatial coverage.
Communication in this band at distances of approximately 50 meters or more, as for example outdoors or in large spaces, typically requires the use of highly directional antennas with gains of 30-40 dB or more to compensate for the attenuation losses. Additionally, there is often a requirement for relatively wide sector coverage to include other devices and stations regardless of location. Some communication systems employ phased array beamforming to steer a relatively narrow beam in a desired direction, but this approach typically requires a number of antenna elements to be coupled to an RF integrated circuit (RFIC) processing chip, where the gain of the phased array is related to the number of antenna elements. It is, however, generally difficult and expensive to couple a sufficient number of antenna elements to provide the necessary gain since the signal routing (feeding lines) between the antenna elements and the RFIC become too complex and result in increased signal attenuation. The cost of these antenna arrays typically grows disproportionately with the number of antenna elements in the array.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art.